Superplasticity of Fine-Grained Titanium Allloys Obtained through Protium Treatment.
Superplasticity of Fine-Grained Titanium Allloys Obtained through Protium Treatment.
复制标题
通过氕处理获得细晶钛合金的超塑性。
DOI：
10.1299/kikaia.66.2247
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
H. Yoshimura
中科院分区：
文献类型：
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作者：
J. Nakahigashi;H. Yoshimura
为了获得氚处理后的细晶α+β型钛合金超塑性的基础数据，在真空条件下进行了超塑性拉伸试验，研究了细晶Ti-6Al-4V合金的延伸率和流变应力随应变速率和温度的变化规律。然后，使用光学显微镜和扫描电子显微镜观察拉伸试验后的显微组织的变化。对粗晶钛合金进行了试验，并与细晶钛合金进行了比较。实验结果表明：晶粒尺寸为1μm ~ 3μm的细晶材料在1123 K和1173 K，应变速率为1×10 ~（-3）S的条件下，延伸率超过3700%。在细晶材料的最大延伸率研究中，当试验温度为1123 K，应变速率为1×10-3S时，材料的最大延伸率超过8008%。细颗粒材料的m值远高于粗颗粒材料，最大m值分别为0.80和0.64。这些结果表明，细晶材料不易发生颈缩。在超塑性拉伸试验后的组织观察中，粗晶材料没有出现晶粒长大，而细晶材料出现了晶粒长大。
To obtain fundamental data on superplasticity of fine-grained α+β type titanium alloys obtained through protium treatment, superplasticity tensile tests were carried out in vacuum, the strain-rate and temperature dependence of elongation and flow stress n fine-grained Ti-6Al-4V alloy were investigated. Then, changes in microstructure after the tensile test were observed using an optical and scanning electron microscope. Coarse-grained titanium alloy was also tested, and compared with fine-grained alloy. Experimental results are as follows:Fine-grained material having a grain size of 1μm to 3μm shows elongation of over 3700% at a testing temperature of 1123 K and 1173K, and a strain rate of 1×10-3S . When the maximum elongation of fine-grained material was investigated, the material showed a huge elongation of more than 8008% at a testing temperature of 1123K and a strain rate of 1×10-3S . The m-value of fine-grained material is much higher than that of coarse-grained material, with the maximum m-values being 0.80 and 0.64 respectively. These results indicate that it is not easy to occur a necking in fine-grained material. In the observation of structure after the superplasticity tensile test, coarse-grained material did not exhibit grain growth, but fine-grained material did.